In the course of completing an oil and/or gas well, it is common practice to run a string of casing into the well bore and then to run production tubing and completion tools inside the casing. It is often necessary to attach centralizers onto the production tubing or completion tool to prevent the tool from being abraded against the side of the casing and to prevent seizure of the tool as it traverses internal casing upsets or deviated casing sections. Most centralizers protect the completion tool by radial fins which are welded or molded onto the body of the centralizer sub or onto a blank tubing portion of the tool. The fins hold the tool substantially centered within the casing bore.